65668820 has 72 divisors (see below), whose sum is σ = 162112104. Its totient is φ = 22278144.

The previous prime is 65668793. The next prime is 65668873. The reversal of 65668820 is 2886656.

65668820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 188356 + 65480464 = 434^2 + 8092^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 110444 + ... + 111036.

It is an arithmetic number, because the mean of its divisors is an integer number (2251557).

Almost surely, 2^65668820 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65668820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81056052).

65668820 is an abundant number, since it is smaller than the sum of its proper divisors (96443284).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65668820 is a wasteful number, since it uses less digits than its factorization.

65668820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 729 (or 720 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 41.

The square root of 65668820 is about 8103.6300507859. The cubic root of 65668820 is about 403.4469198715.

The spelling of 65668820 in words is "sixty-five million, six hundred sixty-eight thousand, eight hundred twenty".